Intervertebral devices and related methods

ABSTRACT

Intervertebral devices and systems, and methods of their use, are disclosed having configurations suitable for placement between two adjacent vertebrae, replacing the functionality of the disc therebetween. Intervertebral devices and systems contemplated herein are implantable devices intended for replacement of a vertebral disc, which may have deteriorated due to disease for example. The intervertebral devices and systems are configured to allow for ample placement of therapeutic agents therein, including bone growth enhancement material, which may lead to better fusion between adjacent vertebral bones. The intervertebral devices and systems are configured for use in minimally invasive procedures, if desired.

This application claims priority to U.S. Provisional Application Ser.No. 61/822,919, entitled “Intervertebral Devices and Related Methods,”filed May 14, 2013, U.S. Provisional Application Ser. No. 61/857,252,entitled “Intervertebral Devices and Related Methods, Filed Jul. 23,2013, and U.S. Provisional Application Ser. No. 61/955,757, entitled“Intervertebral Devices and Related Methods,” filed Mar. 19, 2014, whichapplications are incorporated herein by reference in their entirety.

BACKGROUND

1. Field of this Disclosure

This disclosure relates generally to medical devices, and moreparticularly, to medical devices utilized for spinal procedures.

2. Description of the Related Art

Degenerative disc diseases are common disorders that can impact all or aportion of a vertebral disc, a cushion-like structure located betweenthe vertebral bodies of the spine. Degenerative disc diseases may lead,for example, to a disc herniation where the vertebral disc bulges out orextrudes beyond the usual margins of the disc and the spine. Discherniation, in particular, is believed to be the result of excessiveloading on the disc in combination with weakening of the annulus due tosuch factors as aging and genetics. Such degenerative disc diseases arealso associated with spinal stenosis, a narrowing of the bony andligamentous structures of the spine. Although disc herniation can occuranywhere along the perimeter of the disc, it occurs more frequently inthe posterior and posterior-lateral regions of the disc, where thespinal cord and spinal nerve roots reside. Compression of these neuralstructures can lead to pain, parasthesias, weakness, urine and fecalincontinence and other neurological symptoms that can substantiallyimpact basic daily activities and quality of life.

Temporary relief of the pain associated with disc herniation, or otherdegenerative disc diseases, is often sought through conservativetherapy, which includes positional therapy (e.g. sitting or bendingforward to reduce pressure on the spine), physical therapy, and drugtherapy to reduce pain and inflammation. When conservative therapy failsto resolve a patient's symptoms, surgery may be considered to treat thestructural source of the symptoms. When surgery fails to resolve apatient's symptoms, more drastic measures may include disc replacementsurgery or vertebral fusion.

There are numerous implantable devices that have been developed for discreplacement and vertebral fusion. Such implantable devices, alsoreferred to as cage systems, may be deployed to replace the vertebraldisc and fuse the adjacent vertebrae, relieving pain and providingincreased mobility to the patient. However, known implantable devicesand methodologies have drawbacks. For example, many of the implantabledevices currently available do not allow for an ample amount ofmaterials to encourage bone growth to be positioned within and aroundthe devices and adjacent vertebral bones. Such gone growth materialsallow for a higher level of fusion of the adjacent vertebrae, providingincrease stabilization and minimize the likelihood of further issues inthe future. Also, many implantable devices are large structures that arenot easily utilized in a minimally invasive procedure. Rather, they mayrequire surgical procedures allowing greater access, which subjects thepatient to higher risks of disease and prolonged infection.

There is a need for implantable devices intended for replacement of avertebral disc, which allow for ample placement of bone growth materialthat may lead to better fusion between adjacent vertebral bones. Thereis a further need for such implantable devices to be provided duringminimally invasive procedures, reducing the risk of infection andallowing for quicker healing of the patient.

BRIEF SUMMARY

Consistent with the present disclosure, an expandable intervertebraldevice may comprise a base including a bottom surface configured tointerface with a first biological tissue, a first body portion slidablyattached to the base and configured to move in at least a firstdirection with respect to the base, the first body portion including afirst engaging element, and a second body portion slidably attached tothe base and configured to move in at least a second direction withrespect to the base. The second body portion may include a top surfaceconfigured to interface with a second biological tissue. The base mayinclude a second engaging element such that the second engaging elementcouples to the first engaging element. In certain embodiments, the firstand second engaging elements are configured such that the coupling ofthe first and second engaging elements prevents movement of the secondbody portion in a third direction with respect to the base when acompression force is applied between the top surface of the second bodyportion and the bottom surface of the base. In other embodiments, thethird direction is substantially opposite to the first direction, whilein still other embodiments, the third direction is substantiallyopposite to the first direction.

In yet other embodiments, the first body portion may include a firstsloped surface and the second body portion may include a second slopedsurface. The first sloped surface may be configured to slidably couplewith the second sloped surface, such that movement of the first bodyportion in the first direction results in movement of the second bodyportion in the second direction. The first sloped surface of the firstbody portion may form a first acute angle with respect to a longitudinalaxis of the base, and the second sloped surface of the second bodyportion may form a second acute with respect to the longitudinal axis ofthe base. In some embodiments, the first acute angle is substantiallyequal to the second acute angle, while in other embodiments the firstacute angle is different than the second acute angle. In still otherembodiments, the first sloped surface of the first body portion may forma first acute angle with respect to a longitudinal axis of the base, andthe second sloped surface of the second body portion may form a secondacute with respect to the longitudinal axis of the base. Movement of thesecond body portion relative to the first body portion may define amovement rate, the first and second acute angles may be selected toprovide the movement rate.

In certain embodiments, the first body portion may be configured to beremovably attached to a translating member, where operation of thetranslating member results in movement of the first body portion in thefirst direction, generally along a longitudinal axis of the base. Insome embodiments, the base includes a longitudinal axis, and the firstdirection is substantially parallel to the longitudinal axis of thebase, while in other embodiments, the base includes a longitudinal axis,the second direction being substantially perpendicular to thelongitudinal axis of the base. In other embodiments, the first directionand the second direction are substantially perpendicular.

In still other embodiments, the base includes first and second ends, anda longitudinal axis extending from the first end to the second end, andeach of a plurality of positions of the first body portion along thelongitudinal axis of the base corresponding to a respective one of aplurality of positions of the second body portion. Each of the pluralityof positions of the first body portion may correspond to a respectiveone of a plurality of heights of the intervertebral device.

In yet other embodiments, the first direction is in a direction toward adistal end of the device along a longitudinal axis of the base, while inother embodiments the first direction is in a direction toward aproximal end of the device along a longitudinal axis of the base.

In another aspect, a method includes providing an intervertebral devicehaving a base, a first body portion, and a second body portion, thefirst body portion configured to move in at least a first direction withrespect to the base and the second body portion configured to move in atleast a second direction with respect to the base, the first bodyportion including a first engaging element and the base portionincluding a second engaging element;

moving the first body portion in the first direction, the second bodyportion moving in the second direction in response to movement of thefirst body portion, the first engaging element of the first body portioncouples to the second engaging element of the base, the coupling of thefirst and second engaging elements preventing movement of the secondbody portion in a third direction.

In certain embodiments, the base, and the first and second body portionsform a void, movement of the first body portion in the first directionresults in increasing an area of the void. The method may includedeploying one or more therapeutic agents within the void, thetherapeutic agents including a substance to encourage bone growth, forexample. A central axis of each of the base, and first and second bodyportions may pass through the void.

In other embodiments, moving the first element in the first directionresults in adjusting the height of the intervertebral device. Adjustingthe height may include expanding and contracting the intervertebraldevice.

In yet other embodiments, the first direction is in a direction toward adistal end of the device along a longitudinal axis of the base, while inother embodiments, the first direction is in a direction toward aproximal end of the device along a longitudinal axis of the base.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory onlyand are not restrictive of the any embodiments, as claimed. Otherobjects, features and advantages of the embodiments disclosed orcontemplated herein will be apparent from the drawings, and from thedetailed description that follows below.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference will be made to embodiments of the disclosure, examples ofwhich may be illustrated in the accompanying figures. These figures areintended to be illustrative, not limiting. Although certain aspects ofthe embodiments are generally described in the context of theseembodiments, it should be understood that it is not intended to limitthe scope to these particular embodiments. In the drawings:

FIG. 1 is a perspective view of an intervertebral device in a firstconfiguration.

FIG. 2 is a perspective view of the intervertebral device of FIG. 1 in asecond configuration.

FIG. 3 is a partial section view of the intervertebral device of FIG. 1.

FIG. 4 is another partial section view of the intervertebral device ofFIG. 2.

FIG. 5A is a partial section view of a portion of the intervertebraldevice of FIG. 2.

FIG. 5B is another partial section view of a portion of theintervertebral device of FIG. 2.

FIG. 6 is a portion of the intervertebral device of FIG. 2.

FIG. 7 is a perspective view of another intervertebral device.

FIG. 8 is a partial section view of the intervertebral device of FIG. 1.

FIG. 9 is another partial section view of the intervertebral device ofFIG. 1, in a different configuration.

FIG. 10 is a partial section view of a portion of the intervertebraldevice of FIG. 9.

FIG. 11 is another partial section view of a portion of theintervertebral device of FIG. 9.

FIG. 12 is a perspective view of an intervertebral device in a firstconfiguration.

FIGS. 13A-13C are perspective views of the intervertebral device of FIG.12 in a second configuration.

FIG. 14 is a partial section view of the intervertebral device of FIG.12.

FIG. 15 is a partial section view of the intervertebral device of FIGS.13A-13C.

FIG. 16 is a perspective view of an exemplary delivery device.

FIG. 17 is a perspective view of a portion of the exemplary deliverydevice of FIG. 16.

FIG. 18 is a perspective view of an element of an exemplaryintervertebral device.

FIG. 19 is a partial section view of an interface between the portion ofthe exemplary delivery device of FIG. 17 and an exemplary intervertebraldevice.

FIG. 20 is another partial section view of an interface between theportion of the exemplary delivery device of FIG. 17 and an exemplaryintervertebral device.

FIG. 21 is a perspective view of another exemplary delivery device.

FIG. 22 is a partial section view of a portion of the exemplary deliverydevice of FIG. 21.

FIG. 23 is another partial section view of a portion of the exemplarydelivery device of FIG. 21.

FIG. 24 is a perspective view of a portion of the exemplary deliverydevice of FIG. 21.

FIG. 25 is another partial section view of a portion of the exemplarydelivery device of FIG. 21.

FIG. 26 is a perspective view of another intervertebral device in afirst configuration.

FIGS. 27A and 27B are perspective views of the intervertebral device ofFIG. 26 in a second configuration.

FIG. 28 is a partial section view of the intervertebral device of FIG.26.

FIG. 29 is a partial section view of the intervertebral device of FIG.27A.

FIGS. 30A-30C are perspective views of an exemplary delivery deviceinterfacing with a portion of an exemplary intervertebral device.

FIG. 31 is a top view of another exemplary intervertebral device.

FIG. 32 is a partial section view of the exemplary intervertebral deviceof FIG. 31.

FIG. 33 is another partial section view of the exemplary intervertebraldevice of FIG. 31.

FIG. 34 is a partial section view of another exemplary intervertebraldevice.

FIG. 35 is another partial section view of the exemplary intervertebraldevice of FIG. 34.

FIG. 36 is a perspective view of another exemplary delivery device.

FIG. 37 is a perspective view of a portion of the exemplary deliverydevice of FIG. 36.

FIG. 38 is a top view of an element of the portion of the exemplaryintervertebral device of FIG. 37.

FIG. 39 is a partial section view of the element of the portion of theexemplary intervertebral device of FIG. 37.

FIG. 40 is another top view of an element of the portion of theexemplary intervertebral device of FIG. 37.

FIG. 41 is another partial section view of the element of the portion ofthe exemplary intervertebral device of FIG. 37.

FIGS. 42A-C are perspective views of certain elements of the portion ofthe exemplary delivery device of FIG. 37.

FIG. 43 is a partial section view of a portion of the exemplary deliverydevice of FIG. 36.

FIG. 44 is a perspective view of an element of the exemplary deliverydevice of FIG. 36.

FIGS. 45A-45B are partial section views of portions of the deliverydevice of FIG. 33

FIGS. 46A-46B are perspective views of a portion of the element FIG. 44.

FIG. 47 is a partial cut view of a portion of the element of FIG. 44.

FIG. 48 is a partial section view of a portion of the element of FIG.44.

DETAILED DESCRIPTION

Intervertebral devices and systems, and methods of their use, aredisclosed having configurations suitable for placement between twoadjacent vertebrae, replacing the functionality of the disctherebetween. Intervertebral devices and systems contemplated herein areimplantable devices intended for replacement of a vertebral disc, whichmay have deteriorated due to disease for example. The intervertebraldevices and systems are configured to allow for ample placement oftherapeutic agents therein, including bone growth enhancement material,which may lead to better fusion between adjacent vertebral bones. Theintervertebral devices and systems are configured for use in minimallyinvasive procedures, if desired.

The following description is set forth for the purpose of explanation inorder to provide an understanding of the various embodiments of thepresent disclosure. However, it is apparent that one skilled in the artwill recognize that embodiments of the present disclosure may beincorporated into a number of different systems and devices.

The embodiments of the present disclosure may include certain aspectseach of which may be present in one or more medical devices or systemsthereof. Structures and devices shown below in cross-section or in blockdiagram are not necessarily to scale and are illustrative of exemplaryembodiments. Furthermore, the illustrated exemplary embodimentsdisclosed or contemplated herein may include more or less structuresthan depicted and are not intended to be limited to the specificdepicted structures. While various portions of the present disclosureare described relative to specific structures or processes with respectto a medical device or system using specific labels, such as “locked” or“therapeutic agents”, these labels are not meant to be limiting.

The expandable intervertebral devices described herein may be made fromany suitable biocompatible material, including but not limited tometals, metal alloys (e.g. stainless steel) and polymers (e.g.polycarbonate), and may be formed using any appropriate process, such asscrew-machining or molding (e.g. injection molding). The intervertebraldevices herein may be sized for minimally invasive procedures havingoperating lumens at about 12 mm or less. For illustration purposes only,any expandable intervertebral device described or contemplated hereinmay have a height in the range from about 6 mm to about 16 mm, and alength in the range of from about 20 to about 40 mm, and a width in therange of from about 8 mm to about 16 mm. The intervertebral devicesdescribed or contemplated herein may be positioned between adjacentvertebrae through any suitable procedure, such as through a posteriorlumbar interbody approach or through a transforaminal lumbar interbodyapproach, for example.

Reference will now be made in detail to the present exemplaryembodiments, which are illustrated in the accompanying drawings.

Turning to FIGS. 1 and 2, a perspective view of an exemplaryintervertebral device 100 includes a first element or base element 110,a second or sliding element 140, a third or elevating element 170, and adrive mechanism 190. As will be better understood in the discussionbelow, the elements 110, 140, 170 cooperate such that the intervertebraldevice 100 geometric height, H, may have a minimum, collapsedconfiguration, as generally depicted in FIG. 1, or a maximum, expandedconfiguration, as generally depicted in FIG. 2, or any heighttherebetween, as discussed in greater detail below. As will be betterunderstood in light of the discussion below, the elements 110, 140, 170include protrusions and depressions that cooperate to allow coordinatedmovement of each of the element 110, 140, 170 with respect to eachother. For example, as the second element 140 translates from a proximalposition to a distal position within the first element 110, protrusionsand depressions of the elements 110, 140, 170 cooperate resulting in theelevation of the third element 170 with respect to the first and secondelements 110, 140.

The first element 110 is configured to provide a base or outer structurefor the intervertebral device 100, retaining the remaining elements 140,170 therein. The first element 110 includes a first or proximal end 112and a second or distal end 114 and two side portions, a first sideportion 116 and an opposing side portion 118. A bottom portion 120 ofthe first element 110 may include one or more openings 122 to allow fortherapeutic materials, such as bone growth enhancing materials, to passtherethrough. As used herein, the term “therapeutic materials” ortherapeutic agents” may include any substance, including bone growthmaterials or drug eluding materials for example, or a product or medicaldevice including or deploying such substances, intended for use in themedical diagnosis, cure, treatment, or prevention of disease.

Proximal end 112 of the first element 110 may include an opening 130 forpassing a portion of one or more tools utilized for expanding,contracting, or locking the intervertebral device 100 in a specificconfiguration, as is discussed in greater detail below with reference toFIGS. 3 and 4. For example, the intervertebral device 100 may beexpanded from a first position or configuration, having a height ofH₁₋₁, as depicted in FIG. 1, to a second position or configuration,having a height of H₁₋₂, as depicted in FIG. 2, or any suitable heighttherebetween, and locked in any such configuration or at any suchheight. As used herein, the term “lock”, “locked” or “locking” used inconjunction with the intervertebral device 100, or any otherintervertebral device described or contemplated herein, shall mean tosubstantially maintain the position of each of the main elements, suchas elements 110, 140, 170, with respect to each other. A void or space102 is defined by the elements 110, 140, 170 when the intervertebraldevice 100 takes on a collapsed configured, as depicted in FIG. 1, andthe void or space 102 increases when the intervertebral device 100 takeson an expanded configuration, as depicted in FIG. 2. Therapeutic Agentsmay then be deployed through opening 120, or other suitable opening, tofill the void 102 and expand out of the intervertebral device 100 toengage surrounding tissue, e.g. tissue of the vertebra.

The proximal end 112 of the first element 110 may also includestructures, such as a threaded structure 130T, as better shown in FIGS.3 and 4, and recesses 132, which may allow for an attachment point ofone or more delivery systems, as described in greater detail below withrespect to FIG. 17. Such attachment point may also form the basis for atleast initially positioning the intervertebral device 100, for examplebetween two adjacent vertebrae of a spine. In other embodiments, thedelivery system utilized may include tubular members through whichtherapeutic materials, including bone growth enhancing materials, may beintroduced, for example, to internal voids or spaces within theintervertebral device 100, and exiting through the one or more openings120 of the element 110, or similar openings of the remaining elements140, 170. In this way, such materials may contact surrounding tissues,such as tissues of the vertebrae.

The internal sidewalls of side portions 116, 118 of the first element110 may include one or more protrusions 124 and one or more depressions126, as better viewed with respect to FIG. 5A. These protrusions 124 anddepressions 126 include surfaces that interface with one or moresurfaces of protrusions and depressions of the other elements 140, 170resulting in coordinated movement.

The second element 140 is slidably interfaced to the first element 110such that the second element 140 at least translates horizontally withrespect to the first element 110. Second element 140 may include apositioning structure or pin 145 that is coupled to the second element140. The pin 145 may be configured or adapted to move within a channelor slot 128 provided in the first element 110 to ensure that the secondelement 140 moves in a specific direction with respect to the element110. Accordingly, slot 128 and associated structure or pin 145 may beconfigured to form any desirable angle with respect to a longitudinalcenterline of element 110. As depicted, slot 128 is substantiallyparallel to a longitudinal line of element 110 and, therefore, theelement 130 moves in a direction substantially perpendicular to element110. The second element 140 may also include one or more openings 142that are in fluid communication with openings of one or more otherelements 110, 170, such as openings 122 of the first element 110, toallow for passage of therapeutic agents therethrough.

The third element 170 includes a top surface 171 having one or moreopenings 172 that are in fluid communication with void 102. The topsurface may include other structures to enable or encourage contact andretention with respect to a bodily tissue, such as tissue of a vertebra.The third element 170 may include one or more side members 180, eachhaving one or more protrusions 184 and one or more depressions 186 andcorresponding surfaces that cooperate with surfaces of the first andsecond elements 110, 140 to allow for cooperative movement.

Turning to FIGS. 3 and 4, which depict the intervertebral device 100 incross-section down a central longitudinal axis, drive mechanism 190includes a retaining cap 192 and drive member 194. The drive member 194may include drive points 194D configured to receive a driver forrotational control of the member 194. The retaining cap 192 may befixedly attached to the first element 100 to retain the drive member 194within the intervertebral device 100 and provide a surface force toallow for the translation of the second element 140. For example, asdepicted, the drive member 194 may include a proximal drive point194D_(P) located closer to proximal end 112 of the first element 110,and a distal drive point 194D_(D) located closer to distal end 112 ofthe first element 110. As is discussed in greater detail below, a drivermay enter through opening 130, pass through void 102, and engage theproximal drive point 194D_(P), rotation of the driver resulting incorresponding rotation of the driver member 194, for example. Theretaining cap 192 may include an opening 193 for driver access to thedistal drive point 194D_(D), if desired.

The driver member 194 includes a helical threaded portion 194Tconfigured or adapted to interface with a helical threaded portion 140Tof the second element 140. Accordingly, rotation of the drive member 194results in axial movement of the second member 140. More specifically,if the drive member 194 is rotated in a first direction, the secondelement 140 will move in a distal direction, toward distal end 114 ofthe first element 110, and if the drive member 194 is rotated in asecond opposing direction, the second element 140 will move in aproximal direction, toward proximal end 112 of the first element 110.Since the threads 194T, 140T are continuous, the second element 140 maybe positioned at any point along a longitudinal axis of the firstelement 110, each point along the longitudinal axis corresponding to arespective height of the third element 170.

With specific reference to FIG. 4, depicting the intervertebral device100 in cross-section through a central geometric plane, the secondelement 140 includes side members 150A (not shown) and 150B,collectively referred to as side members 150. As depicted, side member150B includes one or more protrusions 154 and one or more depressions156 that interface with other structures of the third element 170 suchthat when the second element 140 translates distally the third element170 moves at least vertically, increasing an overall height of theintervertebral device 100. For example, protrusion 154 includes a slopedsurface 154 _(S1) that interfaces with an adjacent sloped surface184D_(S3) of the side member 180D of the third element 170. As thesecond element 140 moves distally, the interaction of these slopedsurfaces 154 _(S1), 184D_(S3) results in the vertical displacement ofthe third element 170. The third element 170 may also interface withsloped surfaces of the first element 110 to further encourage thisvertical displacement. For example, the first element 110 includes asloped surface 1105 adjacent to a sloped surface 184D_(S1) associatedwith side member 180D, the interaction of the sloped surfaces 110 _(S),184D_(S1) further encouraging vertical displacement of the third element170 as the second element 140 translates distally within the firstelement 110.

With reference now to FIGS. 5A and 5B, the interaction of first element110 and the third element 170 will be described in greater detail. Fordiscussion purposes only, the second element 140 has been removed.Additionally, while this discussion considers only a single side member180D, this discussion also applies to other side members 180 of thethird element 170. As depicted, side member 180D includes protrusions184D and depressions 186D, the protrusions 184D defining correspondingsurfaces 184D_(S1-S3). The first element 110 includes protrusions 124Band depressions 126B on the inner surface of side portion 118.Protrusion 124B1 includes a surface 124B1 _(S), and protrusion 124B2includes a first surface 124B2 _(S1) and a second surface 124B2 _(S2),surface 184D_(S1) interfacing with surface 124B1 _(S) and surface184D_(S2) interfacing with surface 124B2 _(S1), such that a portion ofside member 180D is able to move within and along depression 126B1. Sidemember 180D also defines a surface 184DS₃ that, along with surface184CS₁ of side member 184C, interfaces with corresponding surfaces ofsecond element 140, as discussed below with reference to FIG. 6.

Turning to FIG. 6, interaction between the geometric features of thesecond element 140 and the third element 170 are depicted and, fordiscussion purposes only, the first element 110 has been removed.Additionally, while this discussion considers only a single side portion150A of the second element 140 and its interaction with side members180A, 180B of the third element 170, this discussion also applies toside portion 150B of the second element 140 and its correspondinginteraction with side members 180C, 180D of the third element 170. Asdepicted, side portion 150A includes first and second protrusions 144A1,144A2, and first and second depressions 146A1, 146A2. The side member180A of the third element 170 includes protrusion 184A having a firstside surface 184A_(S), and a second side surface 184A_(S2). The firstdepression 146A1 of the second element 140 includes a first side surface146A1 _(S1i) and a second side surface 146A1 _(S2). The side member 180Aof the third element 170 is slidably received in the depression 146A1 ofthe second element 140, the surfaces 184A_(S1), 184A_(S2) interfacingwith surfaces 146A1 _(S1), 146A1 _(S2), respectively. Accordingly, asthe second element 140 distally translates in a direction generallydepicted by arrow A_(D), side surface 146A1 _(S1) couples with sidesurface 184A_(S1) to move the third element 170 at least vertically awayfrom the second element 140. Similarly, as the second element 140proximally translates in a direction generally depicted by arrow A_(P),side surface 146A1 _(S2) couples with side surface 184A_(S2) to move thethird element 170 at least vertically toward the second element 140.

Turning to FIG. 7, an exemplary intervertebral device 200 includes afirst element 210, a second element 240, a third element 270, and adrive mechanism 290. Intervertebral device 200 is similar tointervertebral device 100, except the elements 210, 240, 270 of thedevice 200 have geometric characteristics that cooperate in such a wayas to allow, in operation, the third element 270 to move vertically withrespect to a longitudinal axis of the first element 210. The varioussurfaces of the element 110, 140, 170 of the device 100 cooperated toallow, in operation, the third element 170 to move vertically, as wellas horizontally, with respect to a longitudinal axis of the firstelement 110.

Element 210 includes a proximal end 212 and a distal end 214, and afirst side 216 and a second side 218. The element 210 further includes abottom portion 220 having one or more openings 222. The element 210 alsoincludes an opening 230 at the proximal end 212, the opening allowing apassageway for medical tools or therapeutic agents to an interior void202 of the device 200. The second element 240 is similar to element 140,having geometric structures and surfaces that interface with the thirdelement, to allow for the third element to move vertically with respectto a longitudinal axis of the first element 210. The third element 270has a surface 271 adapted to engage a biological tissue surface, theelement 270 including one or more openings 272 in fluid communicationwith the interior void 202 and the one or more openings 222 of thebottom surface 220 of the first element 210. Third element 270 furtherincludes an side member 280B that has vertical surfaces to encouragevertical movement of the third element 270 with respect to the firstelement when operated.

Turning to FIGS. 8 and 9, the intervertebral device 200 is depicted incross-section along a central longitudinal axis. As shown, the device200 includes drive mechanism 290 that includes a retaining cap 292 anddrive member 294, similar to the drive mechanism 190 of theintervertebral device 100. The drive member 294 may include drive points294D configured to receive a driver for rotational control of the member294. The retaining cap 292 may be fixedly attached to the first element200 to retain the drive member 294 within the intervertebral device 200and provide a surface force to allow for the translation of the secondelement 240. For example, as depicted, the drive member 294 may includea proximal drive point 294D_(P) located closer to proximal end 212 ofthe first element 210, and a distal drive point 294D_(D) located closerto distal end 212 of the first element 210. Similar to operation of thedrive mechanism 190, a driver may enter through opening 230, passpartially through void 202, and engage the proximal drive point294D_(P), rotation of the driver resulting in corresponding rotation ofthe driver member 294, for example. The retaining cap 292 may include anopening 293 for driver access to the distal drive point 294D_(D), ifdesired.

The driver member 294 includes a helical threaded portion 294Tconfigured or adapted to interface with a helical threaded portion 240Tof the second element 240. Accordingly, rotation of the drive member 294results in axial movement of the second member 240. More specifically,if the drive member 294 is rotated in a first direction, the secondelement 240 will move in a distal direction, toward distal end 214 ofthe first element 210, and if the drive member 294 is rotated in asecond opposing direction, the second element 240 will move in aproximal direction, toward proximal end 212 of the first element 210.Since the threads 294T, 240T are continuous, the second element 240 maybe positioned at any point along a longitudinal axis of the firstelement 210, each point along the longitudinal axis corresponding to arespective height of the third element 270.

As shown in FIG. 9, the third element 270 includes a side member 280Dthat includes side surfaces which are vertical with respect to alongitudinal axis of the first element 210. The side member 280D, duringoperation, moves vertically in a corresponding depression 218D in theinner wall service of side 218. Turning to FIG. 10, the interaction ofthe first element 210 and the third element 270 of the intervertebraldevice 200 is depicted in greater detail, the second element 240 removedfor discussion purposes only. As shown, the side member 280D is slidablypositioned within the depression 218D. Turning also to FIG. 11, theinteraction between the geometric features of the second element 240 andthe third element 270 are depicted and, for discussion purposes only,the first element 210 has been removed. Additionally, while thisdiscussion considers only a single side portion 250A of the secondelement 240 and its interaction with side members 280A, 280B of thethird element 270, this discussion also applies to side portion 250B ofthe second element 240 and its corresponding interaction with sidemembers 280C, 280D of the third element 270. As depicted, side portion250A includes first and second protrusions 244A1, 244A2, and adepression 246A. The side member 280A of the third element 270 includesprotrusion 284A having a first side surface 284A_(S1) and a second sidesurface 284A_(S2). The depression 246A of the second element 240includes a first side surface 246A_(S1) and a second side surface246A_(S2). The side member 280A of the third element 270 is slidablyreceived in the depression 246A of the second element 240, the surfaces284A_(S1), 284A_(S2) interfacing with surfaces 146A_(S1), 146A_(S2),respectively. Accordingly, as the second element 240 distallytranslates, as generally depicted by arrow A_(D), side surface 246A_(S1)couples with side surface 284A_(S1) to move the third element 270vertically away from the second element 240. Similarly, as the secondelement 240 proximally translates in a direction generally depicted byarrow A_(P), side surface 246A_(S2) couples with side surface 284A_(S2)to move the third element 270 vertically toward the second element 140.

Turning to FIG. 12, a third exemplary intervertebral device 300 includesa first element 310, a second element 340, a third element 370, and adrive mechanism 390. Intervertebral device 300 is similar to devices 100and 200, except as the second element 340 translates distally, both thefirst element 310 and the third element 370 move vertically away fromthe second element 340. Turning to FIGS. 13A and 13B, the intervertebraldevice 300 is depicted in an expanded configuration. As shown,protrusions 344 of the second element 340 are configured to be slidablycoupled to corresponding depressions 326 in the first element 310.Additionally, protrusions 384 of side members 380 of the third element370 are configured to be slidably coupled to corresponding depressions346 of the second element 340. In a similar fashion as described withrespect to the first and second devices 100, 200, as the second elementtranslates distally through operation of the drive mechanism 390,creating or enlarging a void 302, the geometric structures and surfacesof the elements 310, 340, 370 cooperate to move both the first element310 and the third element 370 vertically away from the second element340. The configuration of the intervertebral device 300 allows for agreater overall height of device 300 to be achieved with respect to aninitial height. Accordingly, the intervertebral device 300 may beinitially sized to be delivered through minimally invasive means, e.g.positioned through an endoscopic approach. Once positioned theintervertebral device 300 may then be expanded to a desired height.Turning to FIG. 13C, with the device 300 in an expanded configurationand due to the specific design of the geometric structures of theelements 310, 340, 370, a large void 302 can be achieved. This void 302can then be filled with therapeutic agents, to encourage healing and/orbone growth around and to the device 300.

Now turning to FIGS. 14 and 15, additional information regarding theoperation of intervertebral device 300 will be described. FIG. 14depicts the device 300 in cross-section, and in a collapsedconfiguration, while FIG. 15 depicts the device 300 in cross-section,and in an expanded configuration. As shown, intervertebral device 300includes an alternative element 310A within which a distal portion ofthe second element translates. Element 310A is vertically slidable withrespect to the first element 310 and the third element 350. As with thedrive mechanism 190, drive member 394 includes a helical thread 394Tthat interfaces with corresponding helical thread 340T of the secondelement 340. Rotation of the drive member in a first direction resultsin distal movement of the second element 340 with respect to the element310A. Rotation of the drive member in a second opposing directionresults in a proximal movement of the second element 340 with respect tothe element 310A. The second element 340 includes multiples protrusions344B1-344B3, as well as multiple depressions 346B1-346B3, whichinterface or couple with corresponding depressions and protrusions ofthe third element 370 in a similar fashion as describes above withrespect to intervertebral devices 100 and 200. The second element 340includes additional multiple protrusions 344D and depressions 346D onthe opposing surface of side member 340B, which interface or couple withcorresponding protrusions 324B1-B3 and depressions 326B1-B2,respectively. As with other intervertebral devices described ordiscussed herein, the protrusions and depressions of the elements 310,340, 370 cooperate such that as the second element 340 translatesdistally, various surfaces of the protrusions and depressions interfaceor couple such that the first element 310 moves at least vertically awayfrom the second element 340, and the third element 370 moves at leastvertically away in an opposing direction. With the intervertebral device300 in an expanded configuration the void 302 is maximized allowing fortherapeutic agents to be deployed therein, the therapeutic agentsexiting various openings, such as openings 372, 322, to encourage bonegrowth around or adjacent to the device 300. As the second element 340translates in a proximal direction, the protrusions and depressions ofthe elements 310, 340, 370 cooperate to take on a more collapsedconfiguration.

Turning now to FIG. 16, a delivery system 400 may be used to positionintervertebral devices 100, 200, 300, or any other intervertebraldevices discussed or contemplated herein, between two adjacentvertebrae, and adjust the height of the corresponding device 100, 200,300 as desired. While the delivery system 400 is depicted and discussedwith respect to an intervertebral device 100A depicted in FIGS. 18-21,such discussion and corresponding operation applies to anyintervertebral devices any other intervertebral devices discussed orcontemplated herein. The delivery system 400 includes a handle 402,operational controls 404 and an elongated portion 406 ending in a distalportion 408. The distal portion 408 of the delivery system 400 isconfigured to engage and position an intervertebral device, such asdevice 100A, within a patient's body. A first operational control 404Ais coupled to a first elongate member 410A (not shown) extending withinthe elongate portion 406, from the control 404A to the distal end 408, adistal end of the elongate member 410A configured to couple the deliverysystem 400 to the intervertebral device 100A. A second operation control404B is coupled to a second elongate member 410B (not shown) extendingwithin the elongate portion 406, from the control 404B to the distal end408, the distal end of the elongate member 410B configured to operatethe intervertebral device 100A, e.g. adjust a height of the device 100A.

Turning to FIG. 17, the elongate member 410A ends in a threaded portion410AT at the distal portion 408, and elongate member 410B ends in distalportion 412 including a distal driver 412D. The elongate member 410A isrotatably slidable to elongate member 410B. The distal portion 408 mayalso include one or more mating structures 420 for engaging similarmating structures as part of the intervertebral device 110A, one or moremating structures 134 as shown in FIG. 18 for example. The matingstructures 420, 134 enable the delivery system 400 to maintain a desiredorientation with respect to the device 110A. The distal end 408 may alsoinclude further engaging structures, such as threaded portion 410AT ofthe elongate member 410A, to maintain a hold on the device 110A duringpositioning thereof. The distal driver 412D of the distal portion 412may be configured to enter a void within the intervertebral device 100Aand couple with a drive member, e.g. drive member 194 of drive mechanism190A.

Turning to FIG. 19, operation of the first control 404A may act torotate the threaded portion 410AT of the elongate member 410A, thethreaded portion 410AT interfacing to the threaded portion 130T of thefirst element 110A of the intervertebral device 100A to fixedly attachthe device 100A to the delivery system 400. Once the device 100A ispositioned within a body, between adjacent vertebrae for example, thesecond control 404B may be operated to rotate the driver 412D of thedevice 400, rotation of the driver 412D acting to rotate drive member194A resulting in adjustment of the overall height, H, of theintervertebral device 100A, as described above with respect tointervertebral device 100. Turning also to FIG. 20, FIG. 20 depicts theintervertebral device 100A in an expanded configuration, the secondelement 140 moving to a distal end of the first element 110A.

Turning now to FIG. 21, an alternative delivery system 400A is similarto the delivery system 400 of FIG. 16, however includes a third control404C that operates a deflectable distal portion 408A. Turning to FIG.22, control 404C is coupled to the elongate member 406A through threadedportion 404CT that interfaces with threaded portion 406AT. Control 404Cis further coupled to a proximal end of an elongate member 410C.Elongate member 406 is coupled to distal portion 408A through a hinge416. A distal end of the elongate member 410C is coupled to distalportion 408A of delivery system 400A through a hinge 418. Distal portion408A is also coupled to a central lumen of an elongate member 410Athrough gear 414. Accordingly, rotation of the control 404C is convertedinto axial movement of elongate member 410C, which deflects the distalportion 408A with respect to elongate member 406A, as depicted in FIG.23. Elongate member 410A may include a stop 420 to prevent or limitaxial movement of the elongate member 410C, which ultimately limits thedeflection of the distal end 408A.

FIG. 24 depicts the distal portion 408A deflected and placement ofelongate member 410B, which ends in distal portion 412 and driver 412D.As shown, the distal portion 408A includes one or more protrusions 420Awhich are configured to engage corresponding recesses on theintervertebral device, such as device 100 for example. The elongatemember 410B may include a flexible portion positioned adjacent to thegear 414 such that the member 410B bends with the deflection of thedistal portion 408A. FIG. 25 depicts the delivery system 400A interfacedto an exemplary intervertebral device, such as intervertebral device100. The elongate member 410B has been removed for illustration purposesonly. In operation, the driver 412D of the distal end 412 of theelongate member 410B would interface with a drive member of theintervertebral device, the delivery system 400A adjusting a height ofthe intervertebral device, as described above.

Turning to FIGS. 26 and 27A, a perspective view of an exemplaryintervertebral device 500 includes a first element 510, a second element540, and a third element 570. As will be better understood in thediscussion below, the elements 510, 540, 570 cooperate such that theintervertebral device 500 geometric height may have a minimum, collapsedconfiguration, as generally depicted in FIG. 26, and a maximum, expandedconfiguration, as generally depicted in FIG. 27A and discussed ingreater detail below.

The first element 510, which may also referred to as base 510 or baseelement 510, is configured to provide a base or outer structure for theintervertebral device 500, and includes a first end 512, a second end514, and two side portions, a first side portion 516 and an opposingside portion 518. A bottom portion 520 includes one or more openings 522allowing for therapeutic agents or materials, including bone growthenhancing materials, to pass therethrough. It should be readilyunderstood that the second and third elements 540, 570 may also includesimilar openings. A proximal end, e.g. end 512, may include an opening530 for passing a portion of one or more tools utilized for delivery ofsaid therapeutic agents, or expanding, contracting, or locking theintervertebral device 500 in a specific configuration, as is discussedin greater detail below with reference to FIGS. 30A-30C.

The intervertebral device 500 may be expanded or contracted to anysuitable height, H, between a first collapsed height H₅₋₁ and a secondexpanded height H₅₋₂, with reference to FIGS. 26 and 27A, respectively.For example, the intervertebral device 500 may be expanded from a firstposition, having the height of H₅₋₁ in FIG. 26, to a second position,having the height of H₅₋₂ in FIG. 27A, or any height therebetween, andlocked in any position. As stated above, the term “lock”, “locked” or“locking used in conjunction with the intervertebral device 500, orother intervertebral devices described or contemplated herein, shallmean to substantially maintain the position of each of the elements 510,540, 570 with respect to each other. The end 512 may also includestructures, such as threaded structure 530T, which may allow forattachment points to a delivery system, as described above with respectto intervertebral device 100, for example. Such attachment points mayalso form the basis for at least initially positioning theintervertebral device 500, for example positioning the device 500between two adjacent vertebrae. The elements 510, 540, 570 areconfigured to create a void 502 within the intervertebral device 500,the void 502 increasing during expansion of the intervertebral device500 from a collapsed configuration to an expanded configuration, forexample. In other delivery system embodiments, the delivery system mayinclude tubular members through which therapeutic agents may beintroduced, for example, to internal spaces or voids within theintervertebral device 500 and exiting through the one or more openings522 of the element 510, or similar openings of the remaining elements540, 570. In this way, such therapeutic agents may contact surroundingtissues, such as bone tissue of the vertebra.

The third element 570 is slidably interfaced to the first element 510such that the third element 570 at least slides vertically with respectto the first element 510. The third element 570 may include one or moreopenings 572 in a top portion or top surface 571 thereof to allow forpassage or introduction of therapeutic agents therethrough. The topportion 571 may include one or more protrusions 574 that may aide inholding the top portion 571 immobile with respect to adjacent structuresor biological tissue, such as vertebrae structures for example. Whileonly a few protrusions 574 are identified, additional or lessprotrusions 574 may be utilized. Additionally such protrusions, likeprotrusions 574, may be constructed from any biocompatible material andin any suitable form, and may be used with other elements or surfaces ofintervertebral device 500, or any other intervertebral device describedor contemplated herein. For example, sidewalls 516, 518 of element 510may include one or more protrusions (not shown), similar to protrusions574, and a bottom portion 520 of base 510 may include one or moreprotrusions, similar to protrusions 574.

Turning specifically to FIG. 27A, the element 510 may include apositioning structure or protrusion 524 which may be configured oradapted to move within a corresponding channel 576 provided in element570 to ensure that the element 570 moves in a specific direction withrespect to the element 510. Accordingly, channel 576 and associatedstructure 524 may be configured to form any desirable angle with respectto a longitudinal axis of element 510. As depicted, channel 574 issubstantially perpendicular to a longitudinal axis of element 510 and,therefore, the element 570 moves in a direction substantiallyperpendicular to the longitudinal axis of element 510.

Turning to FIG. 27B, the intervertebral device 500 is depicted in anexpanded configuration and the viewpoint is from the first end 512. Theelements 510, 540, 570 are configured such that when in an expandedconfiguration the open space or void 502 is defined, e.g., as seenthrough opening 530 or opening 572. In this way, once the device 500 isdeployed therapeutic agents may be positioned within the void 502 fromthe first end 512 to the second end 514 and into voids of the otherelements 540, 570. Such material may further flow out of the open spacevia additional openings, such as openings 572 and 522, positioned aboutthe elements 510, 540, 570.

Turning to FIG. 28, an elevation view depicting the elements 510, 540,570 in cross-section is shown. The third element 570 may include aplurality of sloped surfaces 578 that are configured or adapted tocontact a respective one of a plurality of sloped surfaces 548 of secondelement 540. Accordingly, as the second element or sliding element 540translates between the first end 512 and the second end 514 of theelement 510, the sloped surfaces 548 contact and slide alongcorresponding respective sloped surfaces 578 of the third element 570resulting in movement of the element 570 in a direction defined bychannel 574, and the sloped surfaces 548, 578. As depicted, translationof sliding element 540 from the first end 512 toward the second end 514results in movement of the element 570 in a vertical direction away fromthe base element 510. Translation of the sliding element 540 from thesecond end 514 toward the first end 512 results in movement of theelement 540 in a vertical direction toward the base element 510.

The first element 510 or base element 510 includes a plurality ofengaging elements 536 that protrude from a top inner surface of thebottom portion 520 of element 510. Second element 540 includes aplurality of engaging elements 550, at least one engaging a respectiveone of the plurality of engaging elements 536. While depicted as beingintegral to the respective elements 510, 540, the engaging elements 536,550 may be individual parts attached or affixed to the surfaces of thebase element 510 and sliding element 540, respectively. The engagingelements 536, 550 are depicted as having similar shapes, e.g.,triangular portions, however in other configurations, the shapes can bedissimilar. For example, each of the engaging elements 550 may include aconcave surface while each of the engaging elements 536 may include acorresponding mating convex surface. The shapes of the engaging elements536, 550 may also be non-mating surfaces such that gaps exist at theinterface between the engaging elements 536, 550, for example. Also,while depicted as triangular structures, each of the elements 536, 550may be nonsymmetrical along its vertical central axis, passing throughthe tip of each element 536, 550.

The intervertebral device 500 is configured such that applying a lateralforce to the sliding element 540 to translate the element 540 betweenthe first and second ends 512, 514 of base member 510, results in eachengaging element 550 sliding up and over a corresponding engagingelement 536, and engaging an adjacent engaging element 536 in thedirection of the movement of sliding element 540. Accordingly, slidingelement 540, while primarily moving along the longitudinal axis of thebase element 510, also move vertically in accordance with the geometryoutline and coupling of the engaging elements 550, 536 of the slidingelement 540 and base element 510, respectively.

Turning back to FIGS. 26 and 27A, a plurality of pins 544 are coupled tosliding member 540 and extend through corresponding openings 528 in theside portions 516, 518 of base element 510. With the intervertebraldevice 500 in the collapsed configuration, as depicted in FIG. 26, thesliding element 540 is nearer the first end 512, the pins 544 beingnearer the first end 512, as well. With the intervertebral device 500 inthe expanded configuration, as depicted in FIG. 27A, the sliding element540 is nearer the second end 514, the pins 544 being nearer the secondend 514 as well. The openings 523 of the first element 510 are spaced toallow some vertical travel of the sliding element 540 and pins 544 inaccordance with the geometrical shapes, e.g. height, of the engagingelements 550, 536. It is noted that by adjusting the slope of each sidesurface of the engaging elements 550, 536 the translational force tomove the sliding element 540 in the presence of a compression forcebetween the top portion 571 of element 570 and the bottom portion 520 ofthe base element 510 may differ in accordance with the correspondingelement 550, 536 sloped surfaces. The slopes of each side surface of theengaging elements 550, 536, which may be continuous or may not becontinuous, may be configured to encourage movement of the slidingelement 540 in a first direction along the longitudinal axis of the base510 and discourage movement of the sliding element 540 in a secondopposite direction. In any case, the engaging elements 550, 536 areconfigured, e.g., with suitable sloped surfaces or the like, to becomelocked or immovable when a compression force exists between the thirdelement 570 and the base element 510.

Turning now to FIG. 29, the intervertebral device 500 is depicted in anexpanded configuration. With a lateral force applied to sliding element540 moving the element 540 toward end 514, in a ratcheting manner, forexample, the engaging elements 550, 536 continuously engage anddisengage with adjacent opposing engaging elements 550, 536. As theelement 540 translates, the third element 570 moves vertically toincrease the overall height of the device 500. With a compression forceapplied between the third element 570 and the base element 510, e.g.when the device 500 is positioned between adjacent tissue surfaces, suchas two adjacent vertebrae, the engaging elements 550, 536 of the slidingelement 540 and base element 510, respectively, engage and prevent thesliding element 540 to translate further.

Turning to FIGS. 30A-30C, an exemplary tool 600 utilized to translatesliding element 540, or similar sliding elements discussed or describedherein, includes a distal end 602 having a protrusion 604 adjacent to agroove 606. The protrusion is adapted to fit a groove 566 at a proximalend of the sliding element 540. As depicted in FIG. 30A, the tool 600 isangled or rotated along its axis such that the protrusion 604 freelyenters the proximal end of the sliding element 540, as depicted in FIG.30B. Once inserted, the tool 600 may be rotated in a direction indicatedby arrow 30A such that the protrusion 604 is positioned within thegroove 566 of the proximal end of the sliding element 540 and held inplace through the cooperation of the protrusion 604 and a protrusion 567at the proximal end of sliding element 540, as depicted in FIG. 30C.

The groove 566 of the sliding element 540 cooperates with the protrusion604 of the tool 600 to rigidly attach the tool 600 to the element 540.Once the tool 600 is rigidly attached to the sliding element 540 a usercan translate the sliding element 540 through corresponding translationof the tool 600. As described above, translation of the tool 600, whichresults in the translation of the sliding element 540, further resultsin the sliding element 540 to move between the ends 512, 514 of the basemember 510. As the sliding element 540 translates or moves between theends 512, 514, the element 570 moves in a vertical direction withrespect to the base element 510 to change the overall height, H, of theintervertebral device 500. As should be readily understood, the tool 600may extend from a point within a body structure to a point outside ofthe body.

Turning now to FIG. 31, another exemplary intervertebral device 700includes a first or base element 710, a second, or sliding element 740,and a third element 770. The intervertebral device 700 is similar to theintervertebral device 500, but the elements 710, 740, 770 of the device700 include different geometric structures as compared to intervertebraldevice 500. The intervertebral device 700 includes a distal end 712 anda proximal end 714, the distal end 712 including a different geometricstructure used for positioning and operating the device 700.

Turning to FIGS. 32 and 33, a perspective view of the exemplaryintervertebral device 700 is depicted in cut view along section A-A ofFIG. 31. As with other intervertebral device described or contemplatedherein and better understood in light of the discussion below, theelements 710, 740, 770 cooperate such that the intervertebral device 700geometric height, H₇, may have a minimum, collapsed configuration, asgenerally depicted in FIG. 32, and a maximum, expanded configuration, asgenerally depicted in FIG. 33 and discussed in greater detail below.

The first element 710, also referred to as base 710 or base element 710,is configured to provide a base or outer structure for theintervertebral device 700, and includes first end 712, second end 714,and two side portions, a first side portion 716 and an opposing sideportion 718. A bottom portion 720 includes one or more openings 722allowing for therapeutic agent to pass therethrough. It should bereadily understood that the second and third elements 740, 770 may alsoinclude similar openings. The proximal end 712, may include an opening730 for passing a portion of one or more tools utilized for delivery ofsaid therapeutic materials, or expanding, contracting, or locking theintervertebral device 700 in a specific configuration.

The intervertebral device 700 may be expanded or contracted to anysuitable height, H₇, between a first collapsed height H₇₋₁ and a secondexpanded height H₇₋₂, with reference to FIGS. 32 and 33, respectively.For example, the intervertebral device 700 may be expanded from a firstposition, having the height of H₇₋₁ in FIG. 32, to a second position,having the height of H₇₋₂ in FIG. 33, or another position therebetween,and locked in the position. The proximal end 712 may also includestructures, such as protrusions 730P and grooves 730G, which may allowfor attachment points to a delivery system (not shown), as describedbelow with respect to delivery device 800 of FIG. 38. Such attachmentpoints may also form the basis for at least initially positioning theintervertebral device 700, for example between two adjacent vertebrae.As described in greater detail below, the delivery system 800 mayinclude tubular members through which therapeutic agents may beintroduced, for example, to internal spaces within the intervertebraldevice 700 and exiting through the one or more openings 722 of theelement 710, or similar openings of the remaining elements 740, 770. Inthis way, such agents or materials may contact surrounding tissues, suchas bone tissue.

The third element 770 is slidably interfaced to the first element 710such that the third element 770 at least slides vertically with respectto the first element 710. The third element 770 may include one or moreopenings 772 in a top portion 771 thereof to allow for passage orintroduction of therapeutic elements or bone growth enhancing materialstherethrough. The top portion 771 may include one or more protrusions774 that may aide in holding the top portion 771 immobile with respectto adjacent structures or biological tissue, such as vertebraestructures for example. While only a few protrusions 774 are identified,additional or less protrusions 774 may be utilized. Such protrusionstructures 774 may be constructed from any biocompatible material and inany suitable form and may be applied to any embodiment described orcontemplated herein. Additionally, sidewalls 716 of element 710 mayinclude one or more protrusions (not shown), and a bottom portion 720 ofbase 710 may include one or more protrusions 721. Protrusions 721 may,for example, may be similar to protrusions 774, which may aide inholding a bottom portion 720 immobile with respect to adjacentstructures or biological tissue, such as vertebrae structures forexample.

Turning specifically to FIG. 33, the element 710 may include apositioning structure or protrusion similar to the protrusion 524 of thebase element 510 of device 500, which may be configured or adapted tomove within a corresponding channel similar to the channel 576 providedin element 570 of device 500, to ensure that the element 770 moves in aspecific direction with respect to the element 710. Accordingly, as withthe device 500, the channel and associated structure may be configuredto form any desirable angle with respect to a longitudinal axis ofelement 710. The channel of element 770 is substantially perpendicularto a longitudinal axis of element 710 and, therefore, the element 770moves in a direction substantially perpendicular to the longitudinalaxis of element 710.

As with the intervertebral device 500, a void or space 702 is defined bythe first, second, and third element 710, 740, 770 of the intervertebraldevice 700, the void increasing as the device 700 transitions from acollapsed configuration to an expanded configuration. In this way, oncethe device 700 is deployed therapeutic agents may be positioned withinthe void 702 from the first end 712 to the second end 714. Such agentsmay further flow out of the open space via additional openings, such asopenings 772 and 722, positioned about the elements 710, 740, 770.

Turning back to both FIGS. 32 and 33, the third element 770 may includea plurality of sloped surfaces 778 that are configured or adapted tocontact a respective one of a plurality of sloped surfaces 748 of secondelement 740. Accordingly, as the second element or sliding element 740translates between the first end 712 and the second end 714 of theelement 710, the sloped surfaces 748 contact and slide alongcorresponding respective sloped surfaces 778 of the third element 770resulting in movement of the element 770 in a vertical direction, e.g.defined by a channels and wall structures between the first element 710and the third element 770. As depicted, translation of sliding element740 from the first end 712 toward the second end 714 results in movementof the element 770 in a vertical direction away from the base element710. Translation of the sliding element 570 in a direction from thesecond end 714 toward the first end 712 results in movement of theelement 740 in a vertical direction toward the base element 710.

The first element or base element 710 includes a plurality of engagingelements 736 that protrude from a top inner surface of the bottomportion 720 of element 710. Second element 740 includes a plurality ofengaging elements 750, at least one of the elements 750 engaging arespective one of the plurality of engaging elements 736. While depictedas being integral to the respective elements 710, 740, the engagingelements 736, 750 may be individual parts attached or affixed to thesurfaces of the base element 710 and sliding element 740, respectively.As with the engaging elements 536, 550 of the intervertebral device 500,the engaging elements 736, 750 are depicted as having similar shapes,e.g., triangular portions, however in other configurations, the shapescan be dissimilar, or may be nonsymmetrical along its vertical centralaxis, passing through the tip of each element 736, 750.

As with intervertebral device 500, the intervertebral device 700 isconfigured such that applying a lateral force to the sliding element 740to translate the element 740 between the first and second ends 712, 714of base member 710, results in each engaging element 750 sliding up andover a corresponding engaging element 736, and engaging an adjacentengaging element 736 in the direction of the movement of sliding element740. Accordingly, sliding element 740, while primarily moving along thelongitudinal axis of the base element 710, also move vertically inaccordance with the geometry outline and coupling of the engagingelements 750, 736 of the sliding element 740 and base element 710,respectively.

The intervertebral device 700 further includes a plurality of pins 745coupled to sliding member 740 and extending through correspondingopenings 728 in the side portions 716, 718 of base element 710. With theintervertebral device 700 in the collapsed configuration, as depicted inFIG. 32, the sliding element 740 is nearer the first end 712, the pins745 being nearer the first end 712, as well. With the intervertebraldevice 700 in the expanded configuration, as depicted in FIG. 33, thesliding element 740 is nearer the distal end or second end 714, the pins745 being nearer the second end 714 as well. The openings 728 of thefirst element 710 are spaced to allow some vertical travel of thesliding element 740 and pins 745 in accordance with the geometricalshapes, e.g. height, of the engaging elements 750, 736. It is noted thatby adjusting the slope of each side surface of the engaging elements750, 736 the translational force to move the sliding element 740 in thepresence of a compression force between the top portion 771 of element770 and the bottom portion 720 of the base element 710 may differ inaccordance with the corresponding element 750, 736 sloped surfaces. Theslopes of each side surface of the engaging elements 750, 736, which maybe linear or may be nonlinear, may be configured to encourage movementof the sliding element 740 in a first direction along the longitudinalaxis of the base 710 with respect to the sliding element 740 in a secondopposite direction. In any case, the engaging elements 750, 736 areconfigured, e.g., with suitable sloped surfaces or the like, to becomelocked or immovable when a compression force exists between the thirdelement 770 and the base element 710.

Turning specifically to FIG. 33, the sliding element 740 may include aprotrusion 744 configured or adapted to slidably interface with acorresponding recessed portion or groove 736A along the inner wall ofthe third element 770. The protrusion 744 cooperates with recessedportion 736A such that when the sliding element 740 translates in aproximal direction, in a direction toward proximal end 712 of theintervertebral device for example, the surfaces of the protrusion 744engage surfaces of the recessed portion 736A to encourage the thirdelement 770 to move vertically toward the first element 710.

As with vertebral device 500, in the presence of a lateral force appliedto sliding element 740 moving the element 740 toward end 714, in aratcheting manner, for example, the engaging elements 750, 736continuously engage and disengage with adjacent opposing engagingelements 750, 736. As the element 740 translates, the third element 770moves vertically to increase the overall height, H₇, of the device 700.With a compression force applied between the third element 770 and thebase element 710, e.g. when the device 700 is positioned betweenadjacent tissue surfaces, such as two adjacent vertebrae, the engagingelements 750, 736 of the sliding element 740 and base element 710,respectively, engage and prevent the sliding element 740 from furthertranslating. For illustration purposes only, the sliding element 740 ofthe intervertebral device 700 may be translated through the use of atool, such as exemplary tool 600 described above with respect tointervertebral device 500, the distal portion of the sliding element 740including protrusions and grooves to interface with the tool 600, forexample.

Turning to FIGS. 34 and 35, the intervertebral device 700 is depicted incross-section along section A-A of FIG. 31. The intervertebral device700 is depicted in a collapsed configuration in FIG. 34 and an expandedconfiguration in FIG. 35. In particular, the sliding element 740includes a device 760 to aide in maintaining contact between theengaging element 750, 736 of the sliding element 740 and base element710, respectively. The retention device 760 includes the pin 745A andspring 747, the spring 747 seated in bore 748. As depicted, the pin 745Amay extend from a first opening 723 in side portion 716 to a secondopening 723 in side portion 718 (not shown), similar to openings 128 ofthe intervertebral device of FIG. 1. The pin 745A includes a protrusion762 that extends from a central longitudinal axis of the pin 745A towardthe bottom 720 of the first element 710. In operation, as the slidingelement 740 translates between the two ends 712, 714, the engagingelements 750, 736 repeatedly engage and disengage resulting in thesliding element 740 repeatedly moving vertically away from and toward tothe bottom portion 720 of the base element 710, as described above withrespect to the intervertebral device 500. As the sliding element 740moves away from the base element 710 the ends of the pin 745A engage thetop surfaces of the corresponding openings 723 in respective sideportions 716, 718, acting to compress the spring 747. As the engagingelements 750 of the sliding element 740 pass over the correspondingengaging elements 736 of the base element 710 the spring imparts a forceupon the sliding element 740 to encourage re-engagement of the adjacentengaging elements 750, 736. In this way, the engaging elements 750 arebiased to remain coupled to corresponding engaging elements 736 duringeach movement of the sliding element 740, particularly in a no-loadsituation, where the force between the third element 770 and the firstelement 710 is minimal for examples. Accordingly, when a compressionforce is applied between the top surface 771 of the third element 770and the bottom surface 720 of the base element 710, engaging elements750, 736 maintain the current position of all three element 710, 740,770 and, ultimately, the current height, H₇, of the intervertebraldevice 700.

Turning to FIG. 36, a delivery system 800 for positioning and operatingintervertebral device 700, or other intervertebral devices described orcontemplated herein, includes an attachment assembly 810 and anexpansion tool 860. The attachment assembly 810 is utilized forattaching the intervertebral device, such as intervertebral device 700,to the delivery system 800. The expansion tool 860 is utilized forsetting a height of the intervertebral device 700 once the device 700has been deployed, between adjacent vertebrae for example. Turning toFIG. 37, the attachment assembly 810 includes an interface unit 812, acontrol assembly 820, a grasper unit 840, and an elongate member 814that extends from the control assembly 820 to the grasper unit 840. Theinterface unit 812 is configured to attach the attachment assembly 810to the expansion tool 860, as is discussed in greater detail below. Theelongate member 814 may include one or more lumens or members thereinfor controlling the grasper unit 840 or the intervertebral device 700.

Turning to FIGS. 38-41, operation of the grasper unit 840 will bedescribed in greater detail. The grasper unit 840 includes a housing 842having first and second slots 842 _(S1), 842 _(S2), a control ring 844operational coupled to first and second arms 846A, 846B. The elongatemember 814 is fixedly coupled to the housing 842 via pins 815. Anelongate member 816 passes through a lumen of the elongate member 814,and includes a threaded portion 816T that is rotationally coupled tothreaded portion 844T of the control ring 844. Rotational movement ofthe elongate member 816 is transformed into axial movement of thecontrol ring 844 through treaded portions 816T, 844T. First arm 846Aincludes first and second protrusions 846A_(P1), 846A_(P2) positionedwithin slots 842A_(S1), 842A_(S2), respectively, and a third protrusion846A_(P3) at a distal tip of the arm 846A. Similarly, second arm 846Bincludes first and second protrusions 846B_(P1), 846B_(P2) positionedwithin slots 842B_(S1), 842B_(S2), respectively, and a third protrusion846B_(P3) at a distal tip of the arm 846B. As depicted in FIG. 38, arm846A includes a raised portion 848A configured to engage a surface ofhousing 842. More specifically, the raised portion 848A includes asurface 848A_(S) configured to engage a surface 843A_(S) of the housing.In similar fashion, arm 846B includes a raised portion 848B having asurface 848A_(S) configured to engage a surface 843A_(S) of the housing842. Accordingly, as the housing 842 moves distally relative to the arms846A, 846B, a distance between the protrusions 846A_(P3), 846B_(P3)increases.

FIGS. 38 and 39 depict the arms 846A, 846B in an open configuration,while FIGS. 40 and 41 depict the arms 846A, 846B in a closedconfiguration, the arms 846A, 846B being closer to each other in theopen configuration than in the closed configuration. In operation,rotation of the elongate member 816 in a first direction results inaxial movement of the control ring 844 as indicated by arrow 816A. Sincethe control ring 844 is coupled to the arms 846A, 846B, the arms move inthe same direction as the control ring, and the surfaces 848A_(S),848B_(S) cooperate with surfaces 843A_(S), 843B_(S) of housing 842 tomove the arms apart from each other, e.g., transitioning to a closedconfiguration for example. Continued axial movement of the control ringresults in moving the arms 846A, 846B axially to clamp onto the proximalfeatures 730PA and 730PB. Rotation of the elongate member 816 in asecond direction opposite to the first direction, results in axialmovement of the control ring 844 in a direction opposite to thatindicated by arrow 816A. As the control ring 844 moves distally withrespect to housing 842, as well as arms 846A, 846B, distal surfaces ofprotrusions 846A_(P3), 846B_(P2) engage or cooperate with distalportions of slots 842 _(S2) to deflect the arms inward. Accordingly, themore the arms 846A, 846B move distally with respect to the housing 842,the more the distal protrusions 846AP3, 846BP3 move distally and towardto each other, disengaging from the attachment point, and being freefrom the profile of the protrusions 730PA and 730PB, of theintervertebral device 700.

Turning to FIGS. 42A-42C, the interaction between the control ring 844,arms 846A, 846B, and the elongate member 816 is depicted. The controlring 844 includes first and second “T” slots 845, each coupled to aproximal end of one of the arms 846A, 846B, as depicted in FIG. 42B. Thecoupling point between the slots 845 and the arms 846A, 846B allows forthe distal protrusions 846A_(P3), 846B_(P3) to move toward and away fromeach other to enable a position for coupling between the arms 846A, 846Band the intervertebral device 700. FIG. 42C depicts the control ring 844rotatably coupled to the elongate tube 816.

Turning to FIG. 43, the interface unit 812 is fixedly attached to thecontrol assembly 820, the control assembly 820 fixedly attached toelongate member 814. The control assembly 820 includes a rotatablecontrol 824, a clutch assembly 826, and a spring 828. The rotatablecontrol 824 is rotationally attached to a clutch member 826A, as part ofa clutch assembly 826. A clutch member 826B is rotationally attached toelongate member 816. The spring 828 provides a force to encouragecoupling between clutch member 826A and clutch member 826B at fingers826F. The fingers are configured such that rotation of the rotatablecontrol 824 in a first direction results in constant engagement of thefingers, and rotation of the rotatable control 824 in a second directionopposite to the first direction results in the fingers of clutch member826A slipping past the fingers of clutch member 826B once the rotationaltorque becomes greater than the force applied by the spring 826 on theclutch member 826A. In this way, rotation of the rotatable control 824in the second direction results in the arms 846A, 846B couplings to theattachment point of the intervertebral device 700, withoutover-tightening the connection which may result in undue stress in thedelivery system 800 or the intervertebral device 700, or both.

Turning to FIG. 44, the expansion tool 860 includes a handle or handleportion 862 and an elongate shaft rotatably coupled to the handle 862.The expansion tool 860 is utilized for moving the second element, forexample the second element 730 of the intervertebral device 700, along alongitudinal axis of the first element 710 to set a height of theintervertebral device 700 once the device 700 has been deployed, betweenadjacent vertebrae for example.

Turning to FIGS. 45A and 45B, handle portion 862 includes an interfaceassembly 870 and an attachment control 880. The interface assembly 870is configured to attach or interface the handle portion 862 with theattachment assembly 810. More specifically, the interface assembly 870interfaces with the interface element 812 of the attachment assembly810. The interface assembly 870 includes a pushbutton 872 in a slottedportion 873 of the handle 862. The pushbutton 872 is biased by a spring874, which is positioned within a bore 864 of the handle 862. Withspecific reference to FIG. 45A, when the pushbutton 872 is depressed,compressing the spring 874, the interface element 812 of the attachmentassembly 810 may be positioned within an opening 866 within the handle862. The interface element 812 includes a notch 812N sized to be equalto or greater than a width of the pushbutton 872, such that once theinterface element 812 is positioned within the opening 866 thepushbutton 872 may be released and a portion 872A of the pushbutton 872is positioned within the notch 812N, as depicted in FIG. 45B.

Attachment control 880 is utilized to engage the second element, forexample element 730, with the elongate shaft 900. The control 880includes a lever 882 rotatably coupled to the shaft 900, the lever 882being configured to rotate the shaft to enable engagement of the shaft900 with the second element 740. The control 880 may further include aslide lock 884, which is configured to lock the lever control 882 suchthat the shaft 900 is maintained in a desired rotational orientation,during operation of an intervertebral device for example.

Turning to FIGS. 46A and 46B, a distal end 902 of elongate shaft 900includes a protrusion 904 adjacent to a groove 906. The protrusion 904may be adapted to fit a corresponding groove 740G at a proximal end ofthe sliding element 740. As depicted in FIG. 46A, the shaft 900 isangled or rotated along its axis such that the protrusion 904 freelyenters the proximal end of the sliding element 740. Once inserted, theshaft 900 may be rotated, through operation of the attachment control880 for example, such that the protrusion 904 is positioned within thegroove 740G and held in place through the cooperation of the protrusion904 and a protrusion 740P at the proximal end of sliding or thirdelement 740, as depicted in FIG. 46B.

The groove 740G of the sliding element 740 cooperates with theprotrusion 904 of the shaft 900 to rigidly attach the shaft 900 to theelement 740. Once the shaft 900 is rigidly attached to the slidingelement 740 a user can translate the sliding element 740 throughcorresponding translation of the shaft. Turning to FIGS. 47 and 48, thehandle 862 may also include an axial control 890 configured to translatethe shaft 900 in proximal and distal directions. The axial control 890includes a rotational control 892 having threaded portion 894 thatinterfaces with corresponding threaded portion 862T of the handle 862,the axial control 890 being coupled to the shaft 900. Shaft 900 isaxially coupled, not rotationally coupled, to the rotational control892. Accordingly, the axial control 890 converts rotational movement ofthe control 892 into axial movement of the shaft 900. As the rotationalcontrol 892 is rotated in a first direction the control 892 movesdistally within the handle portion, which acts to move shaft 900distally. As the rotational control 892 is rotated in a second directionthe control 892 moves proximally within the handle portion, which actsto move shaft 900 proximally. Translation of the shaft 900 results inthe translation of the sliding element 740, further resulting in thesliding element 740 moving between the ends 712, 714 of the base member710. As the sliding element 740 translates or moves between the ends712, 714, the element 770 moves in a vertical direction with respect tothe base element 710 to change the overall height, H, of theintervertebral device 700.

The intervertebral devices described herein may be made from anysuitable biocompatible material, including but not limited to metals,metal alloys (e.g. stainless steel) and polymers (e.g. polycarbonate),and may be formed using any appropriate process, such as screw-machiningor molding (e.g. injection molding). The intervertebral devices hereinmay be sized for minimally invasive procedures having operating lumensat about 12 mm or less.

It should be understood that features of any one of the above-describedintervertebral devices described herein may be applied to any other ofthe above-described intervertebral devices, as appropriate. Theintervertebral devices described herein may be made from any suitablebiocompatible material, including but not limited to metals, metalalloys (e.g. stainless steel) and polymers (e.g., polycarbonate), andmay be formed using any appropriate process, such as screw-machining ormolding (e.g., injection molding). The intervertebral devices herein maybe sized for minimally invasive procedures having operating lumens atabout 12 mm or less.

What is claimed is:
 1. A device, comprising: a base including a bottomsurface configured to interface with a first biological tissue; a firstbody portion slidably attached to the base and configured to move in atleast a first direction with respect to the base, the first body portionincluding a first engaging element, a second body portion slidablyattached to the base and configured to move in at least a seconddirection with respect to the base, the second body portion including atop surface configured to interface with a second biological tissue,wherein the base includes a second engaging element, the second engagingelement configured to couple to the first engaging element.
 2. Thedevice of claim 1, wherein the first and second engaging elements areconfigured such that the coupling of the first and second engagingelements prevents movement of the second body portion in a thirddirection with respect to the base when a compression force is appliedbetween the top surface of the second body portion and the bottomsurface of the base.
 3. The device of claim 2, wherein the thirddirection is substantially opposite to the first direction
 4. The deviceof claim 1, wherein the third direction is substantially opposite to thefirst direction.
 5. The device of claim 1, wherein the first bodyportion includes a first sloped surface and the second body portionincludes a second sloped surface, the first sloped surface configured toslidably couple with the second sloped surface, such that movement ofthe first body portion in the first direction results in movement of thesecond body portion in the second direction.
 6. The device of claim 5,wherein the first sloped surface of the first body portion forms a firstacute angle with respect to a longitudinal axis of the base, the secondsloped surface of the second body portion forms a second acute withrespect to the longitudinal axis of the base, the first acute anglebeing substantially equal to the second acute angle.
 7. The device ofclaim 5, wherein the first sloped surface of the first body portionforms a first acute angle with respect to a longitudinal axis of thebase, the second sloped surface of the second body portion forms asecond acute with respect to the longitudinal axis of the base, movementof the second body portion relative to the first body portion being amovement rate, the first and second acute angles being selected toprovide the movement rate.
 8. The device of claim 1, wherein the firstbody portion is configured to be removably attached to a translatingmember, operation of the translating member results in movement of thefirst body portion along a longitudinal axis of the base.
 9. The deviceof claim 1, wherein the base includes a longitudinal axis, the firstdirection being substantially parallel to the longitudinal axis of thebase.
 10. The device of claim 1, wherein the base includes alongitudinal axis, the second direction being substantiallyperpendicular to the longitudinal axis of the base.
 11. The device ofclaim 1, wherein the first direction and the second direction aresubstantially perpendicular.
 12. The device of claim 1, wherein the baseincludes first and second ends, and a longitudinal axis extending fromthe first end to the second end, each of a plurality of positions of thefirst body portion along the longitudinal axis of the base correspondingto a respective one of a plurality of positions of the second bodyportion.
 13. The device of claim 12, wherein each of the plurality ofpositions of the first body portion corresponds to a respective one of aplurality of heights of the device.
 14. The device of claim 1, whereinthe first direction is in a direction toward a distal end of the devicealong a longitudinal axis of the base.
 15. The device of claim 1,wherein the first direction is in a direction toward a proximal end ofthe device along a longitudinal axis of the base.
 16. A method,comprising: providing an intervertebral device having a base, a firstbody portion, and a second body portion, the first body portionconfigured to move in at least a first direction with respect to thebase and the second body portion configured to move in at least a seconddirection with respect to the base, the first body portion including afirst engaging element and the base portion including a second engagingelement; moving the first body portion in the first direction, thesecond body portion moving in the second direction in response tomovement of the first body portion, the first engaging element of thefirst body portion couples to the second engaging element of the base,the coupling of the first and second engaging elements preventingmovement of the second body portion in a third direction.
 17. The methodof claim 16, wherein the base, and the first and second body portionsform a void, movement of the first body portion in the first directionresults in increasing an area of the void.
 18. The method of claim 16,wherein the base, and the first and second body portions form a void,the method including deploying one or more therapeutic agents within thevoid.
 19. The method of claim 18, wherein the one or more therapeuticagents includes a substance to encourage bone growth.
 20. The method ofclaim 18, wherein the base, and the first and second body portions forma void, a central axis of each of the base, and first and second bodyportions passing through the void.
 21. The method of claim 16, whereinmoving the first element in the first direction results in adjusting theheight of the intervertebral device.
 22. The method of claim 21, whereinadjusting the height includes expanding and contracting theintervertebral device.
 23. The method of claim 16, wherein the firstdirection is in a direction toward a distal end of the device along alongitudinal axis of the base.
 24. The method of claim 16, wherein thefirst direction is in a direction toward a proximal end of the devicealong a longitudinal axis of the base.